Dental engine



3 Sheets-Sheet 1.

(No Model.).

R. DE L. KING. DENTAL ENGINE.

No. 500,139. Patented June 27,1893.

ms PETERS 00 morouma, wumxoron, o. c.

(No Model.) 3 Sheets-Sheet 2.

R. DE L. KING.

DENTAL ENGINE.

No. 500,139. Patented June 2'7, 1893.

.A WASNYNGTDN n c (No Model.) 3 Sheets-Sheet 3.

- R. DE L. KING.

DENTAL ENGINE No. 500.139. Patented June 27, 1893.

, Xmmmmx wme UNITED STATES PATENT OFFICE.

ROSWELL DE L. KING, OF NEW YORK, N. Y.

DENTAL ENGINE.

SPECIFICATION forming part of Letters Patent No. 500,139, dated June 27,1893.

Application filed September 24, 1892. Serial 110.446 .749. (No model.)

To aZZ whom it may concern:

Be it known that I, ROSWELL DE L. KING, a citizen of the United States,and a resident of New York, in the county of New York and State of NewYork, have invented certain new and useful Improvements in DentalEngines, of whichthe following is a specification.

This invention relates to improvements in dental engines, and has forits object the production of an engine in which the flexible shaftcarrying the burr, drill, or other tool, will have an unusuallatitude ofmovement in a vertical plane, at the same time relieving the operatorfrom sustaining the weight of the shaft, its tube, and driving pulley,thereby permitting perfect freedom in handling the drill and lesseningthe liability to slipping of the instrument while in contact with atooth,

- caused by the weight of the above enumerated parts.

The invention further consists in the arrangement and combination ofparts making the engine light, strong and durable, and insuring thesmooth and even rotation of the flexible shaft in any position it mayassume. To these ends my said invention consists in the details ofconstruction and in the combination of parts, as hereinafter moreparticularly described and pointed out in the claims.

Referring to the accompanying drawings illustrating my invention, in theseveral figures of which like parts are similarly designated, Figure 1,is a side elevation of the upper part of a'dental engine embodying myinvention, and showing the parts in their normal position, or in a stateof rest. Fig.2, isa top view thereof. Fig. 3, is a top view showing theengine in use and the flexible shaft and its tube in a horizontalposition. Fig. 4, is a similar front elevation. Fig. 5, is an enlargedvertical sectional view of the engine in the position shown in Fig. 1.Fig. 6, is a fragmentary rear elevation, partly in section. Fig. 7, is adetail of the stop device.

It may be stated that the-parts of the engine not particularly shown anddescribed may be of the ordinary and well-known construction. p

a, is a tubular standard having projecting therefrom the adjustable rod12, which is capable of being turned in the standard a, and whichcarries near its head the lateral lugs b, to which the opposite beltpulleys c, are

attached, and also having the tubular or oylindrical cross-piece d,through which passes the horizontal arm 6. The rearward portion of thetube (1, is recessed or cut away for about two-thirds of itscircumference, as shown at d, Fig. 7, and the arm 6, is provided withthe pin or projection e, which,by striking against one side or'the otherof said tube 61, limits the rotary motion of said arm. The forwardportion of arm'e, is provided with a coil spring f, havinga seat at oneend against the tube d, and at the other end against the head of thearm. From the head of said arm 6, extend the V-shaped projections g, atthe outer ends of which are the tubular bearings g, g, through which theusual flexible shaft :0, passes. h, is a belt wheel or pulley secured tothe flexible shaft or, between the tubular bearings g, g", the axis ofsaid pulley being hollow and surrounding said shaft, to which the pulleyis secured .by the screws h, passing through the tapped lugs 71 oneither side of said pulley and impinging against the shaft, (see Fig.5,) which is contained for the greater part of its length in the usualtube 2, having the ordinary metal termination y, of a size to surroundand fit the lower tubular bearing g, making what is known as aslip-joint, and to aid the operator in forming this connection and toprevent his hand-from slipping on the smooth metal, I provide the metalportion y,'with the elliptical projections y.

i, is a tube terminating in a heavy counterbalance t", which is alsopreferably bored to permit the shaft to extend up into it, as shown inFig. 5. By this means an unusual length of shaft may be used, the extralength being utilized in case of breakage.

The rearward portion of arm e, is screwthreaded and has loosely screwedthereon the counterbalancej, having depending therefrom the coiledspring is, which is adjustably secured to the standard a, by the strip(Z, and set screw m.

The operation of my device is as follows z- Motion is communicated tothe belt n, from any suitable source of power, as by a treadle andfly-wheel, or an electric or a water motor, 850., and the said beltpasses over pulleys e,

and around pulley h, thereby giving a'rotary continuous movement.

motion to the shaft w. When the operator raises the free end of the tube5,, from its normal position shown in Fig. 1', the counterbalance 1'',is thrown to a horizontal position, as shown in Figs. 3, 4, and 6, andis stopped by the pin e, on the arm e, coming in contact with one sideor the otherof thetubular.

cross-piece cl. By means of this counterbalance the operator has butlittle weight to hold, and is not obliged to sustain the-long'shaft, itstube and driving pulley against the attraction of gravity, as is now thecase. The engine-may be left in one position and the operator work withequal facility'on either side of the patient, the counterbalance i,sustainingthe weight of the shaft-,tubeand driving pull'ey,,andtheextreme positions of said counterbalance are shown'by full anddottedlines'inFig. 6. Any inequalities in the belt, caused by splicing, &c.,are compensated for by the spring f, which allows the arm e, carryin gthe operating parts a reciprocating motion, and the burr,'drill, orother instrument fastsued to the shaft,,is thus given a steady and Whenthe operator uses. the instrument at an angle. in a horizontal planetothe engine, the red I), isrotatedinr 5 its tubular standard, a,against the tensionofi the spring 7;, twisting said spring to one sideon the other, as shown in Fig.2, and as soon-as the operator releasesthe instrument, said spring is, resumesits normal position, as inFig.1,.the screw connection between arm e, and the balancej, being loose topermit perfect freedom of movement between the said parts, relatively toeach: other, The weight j, and, spring k,

whichis normally at. a slight tension, tends to counterbalance theweightof the forward! portion, of arm e, and, the annexed parts, while,as before stated,the counterbalance '5', relieves theweight, of the tubez,.shaftm, and,

driving pulley; it, but. is notquite equal to the combined Weightofsaid, parts, so that when the operator drops the tube z, it willovercomethe weight '5", and at once assume the pet-pens 4, dieular positionshown'in Fig. 1.

Whatl claim as new,.and desire to secure by Letters Patent, is- 1. In adental engine, a swiveled upright support having a bearing for ahorizontal arm, a l-rotatable arm extending through said .ard,substantially as described for the purposes set forth.

3-. In a dentaltengitne, a tubular standard, 1 an adjn stable rotatablerod. therein, carrying opposite upwardly inclined llugs andt a,tnbullarcross or IT-head; guide. pulleys on: said lugs, and a. horizontal armpassing; through I the T-head and. having atits trout. end, bearin gsfor the, toolashaft; a-ishatt passing through I said bearings, anda beltwheelmounted upon ,the shaft between thabeanings substantially v ,asdescribed.

t. Ina dental engine,,a, tubular. standard, Za rotatable rod,therein,provided with a. tubular crossv head, having a portionofi itscincu-m-@ference cut away in combination with a horilzontal arm; mounted, in:said crosshead, and

: having azipin orproj ectiontworking in said .Jcut away portion.whereby themotion of. the ,said armis limited,substantiallyeasidescribed;

,bearingfor a horizontal arm, a rotatable arm mounted in saidbearingandi carrying at one fend tubular. bearings for a tool shaft;a.tool ,Q shaft mountedin, saidbearings, and carrying i3, beltwhee], incombinatiom witha. weight For counterbalancehavinga tubular. extension(adapted to be passed over onset thebearjings of the shaft,substantiallyasdeseribed ,for thepnrposes set forth,

SignedatNew York, in thetcounty of New j; York and State of New York,this 23d day: of

,Septemben, A, D. 1892., t

' ROSWELL DE L. KIN-G;

Witnessesz.

J. B. SABINE,,

EUGENE V. MYERS.

5. In a dental engine, a support having. a,

